//需求：使用JavaScript渲染课工场首页课程列表
let ul = document.getElementsByTagName('ul')
for (let i = 0; i < ul.length; i++) {
    ul[i].style.textDecoration = 'none'
    ul[i].style.backgroundColor = '#ddd'
    ul[i].style.width = '150px'
    ul[i].style.height = '300px'

    ul[i].style.listStyle = 'none'
}
let li = document.getElementsByTagName('li')
for (let i = 0; i < li.length; i++) {
    li[i].style.width = '150px'
    li[i].style.height = '40px'
    li[i].style.paddingTop = '10px'

}